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La forêt classée de l’Ouémé supérieur au Centre-Bénin est un potentiel puits de carbone en dépit des pressions d’origines anthropiques qui menacent la plupart des écosystèmes forestiers. Cette recherche visait à cartographier la biomasse forestière et le stock de carbone séquestré par les formations végétales de la forêt classée de l’Ouémé supérieur au Bénin. A cet effet, un inventaire forestier a été réalisé dans 73 placeaux circulaires de 18 m de rayon suivant le protocole de l’Inventaire Forestier National (IFN). Les principales données collectées étaient le diamètre et la hauteur des arbres. Les images landsat OLI-TIRS de 2018 à travers le NDVI ont été utilisées en combinaison avec les données de l’inventaire forestier in situ pour la spatialisation de la biomasse et du carbone séquestré. Les résultats obtenus ont révélé que la biomasse totale produite par les arbres dans la forêt classée de l’Ouémé supérieur, avoisine 13 035 694 tonnes avec une quantité totale de carbone séquestrée évaluée à 6 348 383 tonnes. La distribution spatiale de la biomasse et du carbone ont montré de plus fortes quantités de biomasse et de carbone séquestré à l’intérieur de la forêt classée comparativement aux périphéries surtout les zones qui sont situées le long des routes aménagées. Il est alors important d’entreprendre les actions de conservation des formations forestières en vue d’accroître leur potentiel de séquestration de carbone dans l’atténuation des effets des changements climatiques au Bénin. English title: Mapping of forest biomass and assessment of sequestered carbon in the forest reserve of upper Ouémé in Central Benin The Upper Ouémé gazetted forest in Central Benin is a potential carbon sink despite the anthropogenic pressures that threaten most forest ecosystems. This research aims to map the forest biomass and carbon stock sequestered by plant communities in the Upper Ouémé classified forest in Benin. To this end, a forest inventory was carried out in 73 circular plots of 18 m radius following the protocol of the National Forest Inventory (IFN). The main data collected were tree diameter and height. The 2018 OLI-TIRS landsat images through NDVI were used in combination with the in situ forest inventory data for the spatialization of biomass and sequestered carbon. The results obtained show that the total biomass produced by trees in the Upper Ouémé classified forest is around 13 035 694 tonnes with a total amount of sequestered carbon estimated at 6 348 383 tonnes. The spatial distribution of biomass and carbon shows higher amounts of biomass and carbon sequestered inside the gazetted forest compared to the periphery, especially in areas that are located along developed roads. It is therefore important to undertake conservation actions in forest in order to increase their carbon sequestration potential in mitigating the effects of climate change in Benin.

Espace G��ographique et Soci��t�� Marocaine, Vol. 1, No 56 (2022): sp��cial ��tudes africaines IV

Background: It is generally accepted that one of the reasons for the declining effectiveness of vector control tools (LLINs, IRS) is the misuse of these tools. Some people sleep outside while the walls of houses are treated with insecticide to protect people from mosquito bites.Methods:To check whether communities that misuse these tools are more exposed to malaria, we used the technique of direct and participatory observation of sleeping habits and we clocked every 30 min, the activities and positions of the communities from 7pm to 7am. The survey was conducted in 3 departments Northern Benin. These were mainly treatments related to variance analysis and descriptive statistics. Softwares used included SPSS 21, SAS 9.2 and Arcgis 10.4.Results: The study shows that 95% of the villages population included in the study stay in their rooms from 7:00 pm to 7:00 am, and only 5% of household members are outdoors during same time intervals during the harmattan season. On the other hand, during hot weather, there are more households outdoors (37%). Less than 20% of household members are outside their rooms during the harmattan season. This number decreases gradually until 10:00 pm when all of them are inside their rooms.Student Newman Keuls test shows that the household members being inside or outside their rooms does not depend on the urbanization situation of the village, but rather on the period.65% exposed to mosquito bites gave irritation as the main reason for their behavior and 15% because of heat and lack of space. Overall, because of household member mobility and malaria vector behaviors, human exposure to An. gambiae was higher outside than inside, despite all the observed food preferences in the vectors.Conclusion:To curtail residual malaria transmission, it must be prioritized to raise awareness in the best use of the tools and provide other complementary control tools for use outside the home.

Background: It is generally accepted that one of the reasons for the declining effectiveness of vector control tools (LLINs, IRS) is the misuse of these tools. Some people sleep outside while the walls of houses are treated with insecticide to protect people from mosquito bites.Methods:To check whether communities that misuse these tools are more exposed to malaria, we used the technique of direct and participatory observation of sleeping habits and we clocked every 30 min, the activities and positions of the communities from 7pm to 7am. The survey was conducted in 3 departments Northern Benin. These were mainly treatments related to variance analysis and descriptive statistics. Softwares used included SPSS 21, SAS 9.2 and Arcgis 10.4.Results: The study shows that 95% of the villages population included in the study stay in their rooms from 7:00 pm to 7:00 am, and only 5% of household members are outdoors during same time intervals during the harmattan season. On the other hand, during hot weather, there are more households outdoors (37%). Less than 20% of household members are outside their rooms during the harmattan season. This number decreases gradually until 10:00 pm when all of them are inside their rooms.Student Newman Keuls test shows that the household members being inside or outside their rooms does not depend on the urbanization situation of the village, but rather on the period. 65% exposed to mosquito bites gave irritation as the main reason for their behavior and 15% because of heat and lack of space. Overall, because of household member mobility and malaria vector behaviors, human exposure to An. gambiae was higher outside than inside, despite all the observed food preferences in the vectors.Conclusion:To curtail residual malaria transmission, it must be prioritized to raise awareness in the best use of the tools and provide other complementary control tools for use outside the home.

Pour apprecier l’acces a l’eau, l’hygiene et a l’assainissement dans la commune d’Abomey-Calavi, un etat des lieux a ete realise et les facteurs associes en matiere d’eau, d’hygiene et d’assainissement ont ete etudies. De mai 2016 a janvier 2017, une etude transversale et analytique a permis d’administrer un questionnaire structure a 630 individus. SPSS et Epi Info ont servi a analyser les facteurs associes. Les focus groupes ont permis de collecter les donnees qualitatives au sein d’un arrondissement urbain et rural. Un echantillonnage par commodite a permis de selectionner, a partir des menages enquetes, dix participants par arrondissement. La methode de l’analyse du contenu a ete utilisee pour traiter les donnees qualitatives. L’analyse des resultats obtenus revele que 61,9% des menages utilisent une source d’eau amelioree, 87,3% disposent d’installation d’assainissement amelioree, 58,3% et 4,03% disposant respectivement de toilette a chasse mecanique et de toilettes seches ont une installation d’hygiene amelioree. Le milieu de residence (OR : 0,3, IC 95% : [0,61-0,42]) explique l’etat de la source d’eau de boisson. Le niveau d’instruction (OR : 1,18 ; IC 95% :[0,61-2,25]) et la source d’eau de boisson (OR, 5,62, IC 95% :[2,66-11,85]) expliquent l’etat de l’hygiene. La depense journaliere (OR, 0,22, IC 95% : [0,11-0,42]), le milieu de residence (OR : 0,05 ; IC 95% : [0,02-0,20]), le niveau d’instruction (OR, 0,27 ; IC 95% : [0,16-0,47]) et les traits caracteristiques du relief (OR, 0,27 ; IC 95% : [0,07-1,14]) expliquent l’etat de l’assainissement. Il ressort de tout ce qui precede que l’acces a l’eau, l’hygiene et a l’assainissement est acceptable dans la commune d’Abomey-Calavi malgre les disparites entre milieu rural et urbain. Les facteurs associes sont : le niveau d’instruction, la source d’eau de boisson, le niveau economique, le milieu de residence et les traits caracteristiques du relief. To appreciate the access to water, hygiene and sanitation in the commune of Abomey-Calavi, the inventory was carried out and the associated factors in terms of water, hygiene and sanitation have been studied. FromMay 2016 to January 2017, a cross-sectional and analytical study was used to administer a structured questionnaire to 630 individuals. SPSS and Epi Info were used to analyze the associated factors. The focus groups were used to collect qualitative data in an urban and rural district. A convenience sample were used to select, fromthe households surveyed, ten participants per district. The content analysis method was used to process the qualitative data. The analysis of the results obtained reveals that 61.9% of households use an improved water source, 87.3% have improved sanitation facilities, 58.3% and 4.03% have respectively a flush toilet and dry toilets have an improved hygiene facility. The place of residence (OR: 0.3, 95% CI: [0, 61-0, 42]) explains the state of the drinking water source. The level of education (OR: 1,18, 95% CI: :[0,61-2,25]) and the source of drinking water (OR, 5,62, 95% CI: [2,66-11,85]) explain the state of hygiene. Daily expenditure (OR, 0, 22, 95% CI: [0,11-0,42]), place of residence (OR: 0.05, 95% CI [0,02-0,20]), level of education (OR, 0.27, 95% CI: [0,16-0,47]) and the characteristics of the relief (OR, 0.27, 95% CI: [0,07-1,14]) explain the state of sanitation. From all the foregoing, it is clear that access to water, hygiene and sanitation is acceptable in the commune of Abomey-Calavi despite the disparities between rural and urban areas. Associated factors are: educational level, drinking water source, economic level, place of residence, and characteristics of relief.

Introduction: Tobacco use and exposure to tobacco smoke are one of the most preventable causes of death and disability worldwide. The risk is even higher among daily tobacco consumers. The World Health Organization (WHO) recommended that surveillance of major risk factors for non- communicable diseases (NCDs), such as smoking, be imperative to predicting the future burden of NCDs, identifying adequate interventions to decrease future burden and monitor trends. In 2015, a survey on NCD risk factors was conducted in Benin to estimate the prevalence of major NCD risk factors. We analyzed the data from this survey to estimate the prevalence and risk factors associated with daily tobacco consumption in Benin. Methods: A nationwide representative sample of the population was constituted in the 12 departments of Benin. The WHO STEPS wise tool was used to collect data on behavioral and demographic characteristics, including daily tobacco consumption. Tobacco consumption was subdivided into three categories: The daily consumption of tobacco, the daily consumption of smoked tobacco and non-smoked tobacco. Multivariate analysis through the weighted logistic regression was used to identify potential factors associated with daily consumption of tobacco. Results: Over the 5.126 surveyed subjects, 7.49% were daily tobacco consumers, with 3.85% being daily users of smoked tobacco and 4.36% being daily consumers of non-smoked tobacco. Men were more likely to be daily consumers of tobacco compared to women (OR = 7.42; 95%CI = [4.98; 11.06]). Compared to respondents aged 18 to 24, those aged 45 to 54 were five times more likely to consume tobacco (OR = 5.58; 95%IC = [2.71; 11.47]). Respondents residing in the departments of Atacora, Couffo and Borgou were respectively 4.28 times, 3.93 times and 2.63 times more likely to consume tobacco compared to those residing in the department of Alibori. Respondents with no education were more likely to consume tobacco daily compared to respondents who had finished high school or were in university (OR = 3.73; 95%CI = [1.36; 10.23]. Respondents who were overweight were less likely to be daily users of tobacco compared to people with normal weight status (OR = 0.57; 95%CI = [0.34; 0.96]). Conclusion: There is a relatively high prevalence of smoking in Benin, where one out of 8 people, consumes tobacco products daily. Being elderly, male, having no formal education, residing in Atacora, Borgou or Couffo were significantly associated with daily smoking. Prevention actions should thus target those sub-groups of the population.

In Benin, the main cash crop is the cotton of which the level of production is largely insufficient to satisfy the national and International market. The main food crops (corn, cassava, yam, bean, rice, etc.) permit to cover the food needed globally, but remain again extensively on this side of the potentialities offered by the ecological conditions of the country. In the process to increase the agricultural production, the herbicides, insecticides and the fertilizers are used now in higher quantity that in the past. The aim of this work was to assess the level of contamination of fish (Tilapia guineensis) in the Couffo River in Djidja (Benin) by the pesticides. Nine (09) samples of fish (Tilapia guineensis) have been collected in nine (09) points along the Couffo River. The analysis of these fish has been done by gas chromatography after extraction and purification. In fish, the detected concentrations in average ranged between 0.123 µg/kg and 0.191 µg/kg for the glyphosate, from 0.095 to 0.128 µg/kg for the profenofos, between 0.112 and 0.125 µg/kg for the acetamiprid and 0.127 and 0.139 µg/kg. To assess the risk to public health, pesticides intake by fish consumption was estimated and compared with Estimated Daily Intake (EDI) values reported by the Codex Alimentarius. This comparison showed that fish consumption does not pose a risk for public health.

Background: Climate variability influence the diversity and abundance of malaria vectors and thereby on malaria transmission dynamics. Examine its effect on Anopheles parameters involved in transmission may predict the potential malaria hotspot as a right target for its control intervention strategies. Here, we investigated the influence of meteorological parameters on the aggressiveness and infectivity of Anopheles in two health districts zones where IRS has been extended in Northern Benin. Methods: Mosquito collections were carried out using human landing catches to evaluate rates of aggression and infectivity in twelve villages. Concomitantly, meteorological data from synoptic stations of Benin and neighbouring countries were collected in 2016-2017. Results: The spatial distribution of infective bites of An. gambiae is characterized by an intense aggression in the rural villages of the study area. Analysis of variances showed significant HBR difference according to the period but not according to the locality. However, the same analysis carried out with the infectivity rate shows no significant difference according to the period and the locality. In addition, the number of infective bites per man per month is higher in August and October, and the climatic parameters that have mainly favoured aggression are wind speed, humidity, sunshine and temperature. Indeed, the peak of wind speed is concentrated around 1.2 km / h and in September (5 km / h) whereas the aggressiveness score of Anopheles in the region is greater than 10 infective bites per man a year. Conclusion Malaria transmission by Anopheles is influenced by climatic factors. The climate observed in the districts where IRS was extended in northern Benin has a real impact on Anopheles density and weakens current and future vector control strategies. This could lead to a series of modifications observed in anopheline populations just after IRS implementation ranging from a tendency to exophagy, from a decrease in the rate of blood-feeding to changes in the time, and change in aggressiveness. These phenomena most likely contribute to the sustainability of malaria transmission despite vector control measures. Keywords: Infectivity, aggression, Climate, Anopheles gambiae ( s.l. ), IRS, Benin.

Background: Climate variability influence the diversity and abundance of malaria vectors and thereby on malaria transmission dynamics. Examine its effect on Anopheles parameters involved in transmission may predict the potential malaria hotspot as a right target for its control intervention strategies. Here, we investigated the influence of meteorological parameters on the aggressiveness and infectivity of Anopheles in two health districts zones where IRS has been extended in Northern Benin. Mosquito collections were carried out using human landing catches to evaluate rates of aggression and infectivity in twelve villages. Concomitantly, meteorological data from synoptic stations of Benin and neighbouring countries were collected in 2016-2017. The spatial distribution of infective bites of An. gambiae is characterized by an intense aggression in the rural villages of the study area. Analysis of variances showed significant HBR difference according to the period but not according to the locality. However, the same analysis carried out with the infectivity rate shows no significant difference according to the period and the locality. In addition, the number of infective bites per man per month is higher in August and October, and the climatic parameters that have mainly favoured aggression are wind speed, humidity, sunshine and temperature. Indeed, the peak of wind speed is concentrated around 1.2 km / h and in September (5 km / h) whereas the aggressiveness score of Anopheles in the region is greater than 10 infective bites per man a year. Malaria transmission by Anopheles is influenced by climatic factors. The climate observed in the districts where IRS was extended in northern Benin has a real impact on Anopheles density and weakens current and future vector control strategies. This could lead to a series of modifications observed in anopheline populations just after IRS implementation ranging from a tendency to exophagy, from a decrease in the rate of blood-feeding to changes in the time, and change in aggressiveness. These phenomena most likely contribute to the sustainability of malaria transmission despite vector control measures.

This study aimed to analyze the environmental factors related to health vulnerability in the municipality of Seme-Podji. For this study, 216 households were surveyed using questionnaires. Twelve key informants were enrolled for depth interviews and 18 water samples were collected from different sources used by the populations. It came out of our investigations that water from traditional sources used at Seme-Podji was contaminated by various microorganisms such as Escherichia coli and fecal coliforms. 66.38% of households reject domestic waste and 47.41% of them evacuate sewage in the yard. In addition, 93.05% drop stagnant water for natural infiltration. This municipality faces lack of sanitation. The main health problems experienced by people were malaria (46.35%), diarrheal diseases (15.88%). The study stated some results which could improve the help about health management in the area.